Demonstrating the cervicothoracic junction : a comparison of two techniques

Abstract

Motivated by the challenges associated with demonstrating the cervicothoracic junction, a study was conducted at Pelonomi Regional Hospital from May 2006 to June 2007. In this study, two projections of the cervicothoracic junction were done, with the only difference between them being the orientation of the arms. One projection was done using the swimmer’s projection and the other using an adaptation of the swimmer’s projection where the orientation of the arms was reversed. The sample, consisting of 45 patients, was referred from the emergency department and wards. Most of the patients (95.5%) were examined using a computed radiography system providing digital images that were printed using a laser film printer. Other patients were examined using conventional film/screen systems. The objectives of this study were to compare the two imaging techniques with reference to diagnostic quality of the projections, diagnosis of pathology and repeat rate.

Radiographers obtained the two projections of the cervical spine; the researcher collected the images and distributed these to three participating radiologists on a rotational basis. The radiologists evaluated the films using a set of criteria; a biostatistician analysed the results of these evaluations.

In all the criteria of image quality the swimmer’s projection showed better results. There were also, however, instances where the adapted swimmer’s had better results. The differences in percentages were not significant enough to show any statistical difference between the resultant images of the two techniques. No valid deduction could be made in relation to the demonstration of pathology due to variable instances of pathology evaluated by the radiologists. The repeat rate of the adapted swimmer’s projection compared well with the swimmer’s projection.

Though the swimmer’s projection had better results for most of the criteria used in this study, no unequivocal, statistically significant evidence of it demonstrating C7-T1 better could be found. What was evident was the validity of the adapted swimmer’s projection as an alternative under certain conditions. Knowing that there is an alternative method to visualising the C7- T1 junction could be beneficial not only to radiography, but also to our patients. In cases where the swimmer’s projection is not possible due to extremity injuries, an alternative arm orientation can be useful. The alternative can also address the problem regarding multiple repeats of the swimmer’s projection.